/*-
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Chris Torek.
 *
 * Portions copyright (c) 1999, 2000
 * Intel Corporation.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 * 
 *    This product includes software developed by the University of
 *    California, Berkeley, Intel Corporation, and its contributors.
 * 
 * 4. Neither the name of University, Intel Corporation, or their respective
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS, INTEL CORPORATION AND
 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS,
 * INTEL CORPORATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)atexit.c	8.2 (Berkeley) 7/3/94";
#endif /* LIBC_SCCS and not lint */

#include <stddef.h>
#include <stdlib.h>
#include <unistd.h>
#include "atexit.h"

struct atexit *__atexit;	/* points to head of LIFO stack */

/*
 * Register a function to be performed at exit.
 */
int
atexit(fn)
	void (*fn)(void);
{
	static struct atexit __atexit0;	/* one guaranteed table */
	register struct atexit *p;

	if ((p = __atexit) == NULL)
		__atexit = p = &__atexit0;
	else if (p->ind >= ATEXIT_SIZE) {
#if 0
		if ((p = (struct atexit *)sbrk(sizeof(*p))) == (struct atexit *)-1)
#endif
		if ((p = (struct atexit *)malloc(sizeof(*p))) == NULL)
			return (-1);
		p->ind = 0;
		p->next = __atexit;
		__atexit = p;
	}
	p->fns[p->ind++] = fn;
	return (0);
}
